ICD-10 Code L66.2 – Folliculitis decalvans (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code L66.2 – Folliculitis decalvans
What it is
Folliculitis decalvans is a chronic inflammatory scalp disorder that damages hair follicles and can lead to scarring hair loss. The code identifies this specific cicatricial alopecia pattern.
Clinical signs
Typical findings include scalp inflammation, pustules, crusting, and patchy hair loss with scarring. Clinical features vary; refer to documentation.
When to use this code
Use L66.2 when the clinician documents folliculitis decalvans, including cases described as scarring alopecia caused by this condition. It is also appropriate when the record clearly names the disorder on dermatology assessment or pathology-supported documentation. Do not code from nonspecific hair loss alone.
Do not use for
Do not use this code for ordinary folliculitis, nonscarring alopecia, or hair loss without documentation of folliculitis decalvans. Check documentation if the diagnosis is unclear.
Coding tip
Assign L66.2 only when the provider explicitly documents folliculitis decalvans or an equivalent diagnosis.